import java.util.Scanner;

public class Test {
    public static void main(String[] args) {
       Scanner scanner = new Scanner(System.in);
            int n = scanner.nextInt();
           int flg=1;
            for (int i = 2;i <= Math.sqrt(n);i++) {
                if(n%i == 0) {
                 flg=0;
                    break;
                }
            }
            if(flg==1) {
                System.out.println(n + "是素数");
            }
        else{
                System.out.println(n+"不是素数");
            }



    }

}
